[PATCH v3 01/10] of_net: add NVMEM support to of_get_mac_address

[PATCH v3 01/10] of_net: add NVMEM support to of_get_mac_address

[Petr Štetiar]

Many embedded devices have information such as MAC addresses stored
inside NVMEMs like EEPROMs and so on. Currently there are only two
drivers in the tree which benefit from NVMEM bindings.

Adding support for NVMEM into every other driver would mean adding a lot
of repetitive code. This patch allows us to configure MAC addresses in
various devices like ethernet and wireless adapters directly from
of_get_mac_address, which is already used by almost every driver in the
tree.

Predecessor of this patch which used directly MTD layer has originated
in OpenWrt some time ago and supports already about 497 use cases in 357
device tree files.

Cc: Alban Bedel <albeu@free.fr>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
---

 Changes since v1:

  * moved handling of nvmem after mac-address and local-mac-address properties

 Changes since v2:

  * moved of_get_mac_addr_nvmem after of_get_mac_addr(np, "address") call
  * replaced kzalloc, kmemdup and kfree with it's devm variants
  * introduced of_has_nvmem_mac_addr helper which checks if DT node has nvmem
    cell with `mac-address`
  * of_get_mac_address now returns ERR_PTR encoded error value

 drivers/of/of_net.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 62 insertions(+), 3 deletions(-)

diff --git a/drivers/of/of_net.c b/drivers/of/of_net.c
index d820f3e..258ceb8 100644
--- a/drivers/of/of_net.c
+++ b/drivers/of/of_net.c
@@ -8,8 +8,10 @@
 #include <linux/etherdevice.h>
 #include <linux/kernel.h>
 #include <linux/of_net.h>
+#include <linux/of_platform.h>
 #include <linux/phy.h>
 #include <linux/export.h>
+#include <linux/device.h>
 
 /**
  * of_get_phy_mode - Get phy mode for given device_node
@@ -47,12 +49,59 @@ static const void *of_get_mac_addr(struct device_node *np, const char *name)
 	return NULL;
 }
 
+static const void *of_get_mac_addr_nvmem(struct device_node *np)
+{
+	int ret;
+	u8 mac[ETH_ALEN];
+	struct property *pp;
+	struct platform_device *pdev = of_find_device_by_node(np);
+
+	if (!pdev)
+		return ERR_PTR(-ENODEV);
+
+	ret = nvmem_get_mac_address(&pdev->dev, &mac);
+	if (ret)
+		return ERR_PTR(ret);
+
+	pp = devm_kzalloc(&pdev->dev, sizeof(*pp), GFP_KERNEL);
+	if (!pp)
+		return ERR_PTR(-ENOMEM);
+
+	pp->name = "nvmem-mac-address";
+	pp->length = ETH_ALEN;
+	pp->value = devm_kmemdup(&pdev->dev, mac, ETH_ALEN, GFP_KERNEL);
+	if (!pp->value) {
+		ret = -ENOMEM;
+		goto free;
+	}
+
+	ret = of_add_property(np, pp);
+	if (ret)
+		goto free;
+
+	return pp->value;
+free:
+	devm_kfree(&pdev->dev, pp->value);
+	devm_kfree(&pdev->dev, pp);
+
+	return ERR_PTR(ret);
+}
+
+static inline bool of_has_nvmem_mac_addr(struct device_node *np)
+{
+	int index = of_property_match_string(np, "nvmem-cell-names",
+					     "mac-address");
+	return of_parse_phandle(np, "nvmem-cells", index) != NULL;
+}
+
 /**
  * Search the device tree for the best MAC address to use.  'mac-address' is
  * checked first, because that is supposed to contain to "most recent" MAC
  * address. If that isn't set, then 'local-mac-address' is checked next,
- * because that is the default address.  If that isn't set, then the obsolete
- * 'address' is checked, just in case we're using an old device tree.
+ * because that is the default address. If that isn't set, then the obsolete
+ * 'address' is checked, just in case we're using an old device tree. If any
+ * of the above isn't set, then try to get MAC address from nvmem cell named
+ * 'mac-address'.
  *
  * Note that the 'address' property is supposed to contain a virtual address of
  * the register set, but some DTS files have redefined that property to be the
@@ -64,6 +113,9 @@ static const void *of_get_mac_addr(struct device_node *np, const char *name)
  * addresses.  Some older U-Boots only initialized 'local-mac-address'.  In
  * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
  * but is all zeros.
+ *
+ * Return: Will be a valid pointer on success, NULL in case there wasn't
+ *         'mac-address' nvmem cell node found, and ERR_PTR in case of error.
 */
 const void *of_get_mac_address(struct device_node *np)
 {
@@ -77,6 +129,13 @@ const void *of_get_mac_address(struct device_node *np)
 	if (addr)
 		return addr;
 
-	return of_get_mac_addr(np, "address");
+	addr = of_get_mac_addr(np, "address");
+	if (addr)
+		return addr;
+
+	if (!of_has_nvmem_mac_addr(np))
+		return NULL;
+
+	return of_get_mac_addr_nvmem(np);
 }
 EXPORT_SYMBOL(of_get_mac_address);
-- 
1.9.1

Re: [PATCH v3 01/10] of_net: add NVMEM support to of_get_mac_address

[Sergei Shtylyov]

Hello!

On 03.05.2019 10:55, Petr Štetiar wrote:

> Many embedded devices have information such as MAC addresses stored
> inside NVMEMs like EEPROMs and so on. Currently there are only two
> drivers in the tree which benefit from NVMEM bindings.
> 
> Adding support for NVMEM into every other driver would mean adding a lot
> of repetitive code. This patch allows us to configure MAC addresses in
> various devices like ethernet and wireless adapters directly from
> of_get_mac_address, which is already used by almost every driver in the
> tree.
> 
> Predecessor of this patch which used directly MTD layer has originated
> in OpenWrt some time ago and supports already about 497 use cases in 357
> device tree files.
> 
> Cc: Alban Bedel <albeu@free.fr>
> Signed-off-by: Felix Fietkau <nbd@nbd.name>
> Signed-off-by: John Crispin <john@phrozen.org>
> Signed-off-by: Petr Štetiar <ynezz@true.cz>
> ---
> 
>   Changes since v1:
> 
>    * moved handling of nvmem after mac-address and local-mac-address properties
> 
>   Changes since v2:
> 
>    * moved of_get_mac_addr_nvmem after of_get_mac_addr(np, "address") call
>    * replaced kzalloc, kmemdup and kfree with it's devm variants
>    * introduced of_has_nvmem_mac_addr helper which checks if DT node has nvmem
>      cell with `mac-address`
>    * of_get_mac_address now returns ERR_PTR encoded error value
> 
>   drivers/of/of_net.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++---
>   1 file changed, 62 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/of/of_net.c b/drivers/of/of_net.c
> index d820f3e..258ceb8 100644
> --- a/drivers/of/of_net.c
> +++ b/drivers/of/of_net.c
[...]
> @@ -64,6 +113,9 @@ static const void *of_get_mac_addr(struct device_node *np, const char *name)
>    * addresses.  Some older U-Boots only initialized 'local-mac-address'.  In
>    * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
>    * but is all zeros.
> + *
> + * Return: Will be a valid pointer on success, NULL in case there wasn't
> + *         'mac-address' nvmem cell node found, and ERR_PTR in case of error.

    Returning both NULL and error codes on failure is usually a sign of a 
misdesigned API. Why not always return an error code?

[...]

MBR, Sergei

Re: [PATCH v3 01/10] of_net: add NVMEM support to of_get_mac_address

[Petr Štetiar]

Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> [2019-05-03 11:44:54]:

Hi Sergei,

> > diff --git a/drivers/of/of_net.c b/drivers/of/of_net.c
> > index d820f3e..258ceb8 100644
> > --- a/drivers/of/of_net.c
> > +++ b/drivers/of/of_net.c
> [...]
> > @@ -64,6 +113,9 @@ static const void *of_get_mac_addr(struct device_node *np, const char *name)
> >    * addresses.  Some older U-Boots only initialized 'local-mac-address'.  In
> >    * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
> >    * but is all zeros.
> > + *
> > + * Return: Will be a valid pointer on success, NULL in case there wasn't
> > + *         'mac-address' nvmem cell node found, and ERR_PTR in case of error.
> 
>    Returning both NULL and error codes on failure is usually a sign of a
> misdesigned API. 

well, then there's a lot of misdesigned APIs in the tree already, as I've just
grepped for IS_ERR_OR_NULL usage and found this pointer/NULL/ERR_PTR usage
pretty legit.

> Why not always return an error code?

I've received following comment[1] from Andrew:

 "What you have to be careful of, is the return value from your new code
  looking in NVMEM. It should only return EPROBE_DEFER, or another error
  if there really is expected to be a value in NVMEM, or getting it from
  NVMEM resulted in an error."

So in order to fullfil this remark, I can't simply use ENOENT instead of
current NULL, as the caller couldn't distinguish between ENOENT from
of_get_mac_address or ENOENT from NVMEM subsystem.

1. https://patchwork.ozlabs.org/patch/1092243/#2161764

-- ynezz

Re: [PATCH v3 01/10] of_net: add NVMEM support to of_get_mac_address

[Maxime Ripard]

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On Fri, May 03, 2019 at 11:15:42AM +0200, Petr Štetiar wrote:
> Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> [2019-05-03 11:44:54]:
>
> Hi Sergei,
>
> > > diff --git a/drivers/of/of_net.c b/drivers/of/of_net.c
> > > index d820f3e..258ceb8 100644
> > > --- a/drivers/of/of_net.c
> > > +++ b/drivers/of/of_net.c
> > [...]
> > > @@ -64,6 +113,9 @@ static const void *of_get_mac_addr(struct device_node *np, const char *name)
> > >    * addresses.  Some older U-Boots only initialized 'local-mac-address'.  In
> > >    * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
> > >    * but is all zeros.
> > > + *
> > > + * Return: Will be a valid pointer on success, NULL in case there wasn't
> > > + *         'mac-address' nvmem cell node found, and ERR_PTR in case of error.
> >
> >    Returning both NULL and error codes on failure is usually a sign of a
> > misdesigned API.
>
> well, then there's a lot of misdesigned APIs in the tree already, as I've just
> grepped for IS_ERR_OR_NULL usage and found this pointer/NULL/ERR_PTR usage
> pretty legit.

That's not really an argument though.

> > Why not always return an error code?
>
> I've received following comment[1] from Andrew:
>
>  "What you have to be careful of, is the return value from your new code
>   looking in NVMEM. It should only return EPROBE_DEFER, or another error
>   if there really is expected to be a value in NVMEM, or getting it from
>   NVMEM resulted in an error."
>
> So in order to fullfil this remark, I can't simply use ENOENT instead of
> current NULL, as the caller couldn't distinguish between ENOENT from
> of_get_mac_address or ENOENT from NVMEM subsystem.

Does it matter? You're trying to put some specific code (nvmem lookup)
behind a generic API, so the fact that you get some nvmem related
errors is more an abstraction leakage than anything else.

And if you don't really like ENOENT, ENODEV is an option as well.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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Re: [PATCH v3 01/10] of_net: add NVMEM support to of_get_mac_address

[Andrew Lunn]

On Fri, May 03, 2019 at 11:15:42AM +0200, Petr Štetiar wrote:
> Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> [2019-05-03 11:44:54]:
> 
> Hi Sergei,
> 
> > > diff --git a/drivers/of/of_net.c b/drivers/of/of_net.c
> > > index d820f3e..258ceb8 100644
> > > --- a/drivers/of/of_net.c
> > > +++ b/drivers/of/of_net.c
> > [...]
> > > @@ -64,6 +113,9 @@ static const void *of_get_mac_addr(struct device_node *np, const char *name)
> > >    * addresses.  Some older U-Boots only initialized 'local-mac-address'.  In
> > >    * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
> > >    * but is all zeros.
> > > + *
> > > + * Return: Will be a valid pointer on success, NULL in case there wasn't
> > > + *         'mac-address' nvmem cell node found, and ERR_PTR in case of error.
> > 
> >    Returning both NULL and error codes on failure is usually a sign of a
> > misdesigned API. 
> 
> well, then there's a lot of misdesigned APIs in the tree already, as I've just
> grepped for IS_ERR_OR_NULL usage and found this pointer/NULL/ERR_PTR usage
> pretty legit.
> 
> > Why not always return an error code?
> 
> I've received following comment[1] from Andrew:
> 
>  "What you have to be careful of, is the return value from your new code
>   looking in NVMEM. It should only return EPROBE_DEFER, or another error
>   if there really is expected to be a value in NVMEM, or getting it from
>   NVMEM resulted in an error."
> 
> So in order to fullfil this remark, I can't simply use ENOENT instead of
> current NULL, as the caller couldn't distinguish between ENOENT from
> of_get_mac_address or ENOENT from NVMEM subsystem.

ENOENT and its like have to be handled special by of_get_mac_address()
for all the different ways you can find the MAC address. It means that
method does not have a MAC address, try the next. And if at the end
you have not found a MAC address, ENOENT is a good return code, it
indicates none of the methods found a MAC address.

If you are using of_get_mac_address() you don't really care where the
MAC address came from, except you expect the documented search order.
So you don't need to know that NVMEM returned ENOENT. If you do care
about that, you would not use of_get_mac_address(), but directly go to
the NVMEM.

    Andrew

[PATCH v3 02/10] dt-bindings: doc: reflect new NVMEM of_get_mac_address behaviour

[Petr Štetiar]

As of_get_mac_address now supports NVMEM under the hood, we need to update
the bindings documentation with the new nvmem-cell* properties, which would
mean copy&pasting a lot of redundant information to every binding
documentation currently referencing some of the MAC address properties.

So I've just removed all the references to the optional MAC address
properties and replaced them with the small note referencing
net/ethernet.txt file.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---

 Changes since v2:

 * replaced only MAC address related optional properties with a text
   referencing ethernet.txt

 Documentation/devicetree/bindings/net/altera_tse.txt           |  5 ++---
 Documentation/devicetree/bindings/net/amd-xgbe.txt             |  5 +++--
 Documentation/devicetree/bindings/net/brcm,amac.txt            |  4 ++--
 Documentation/devicetree/bindings/net/cpsw.txt                 |  4 +++-
 Documentation/devicetree/bindings/net/davinci_emac.txt         |  5 +++--
 Documentation/devicetree/bindings/net/dsa/dsa.txt              |  5 ++---
 Documentation/devicetree/bindings/net/ethernet.txt             |  6 ++++--
 Documentation/devicetree/bindings/net/hisilicon-femac.txt      |  4 +++-
 .../devicetree/bindings/net/hisilicon-hix5hd2-gmac.txt         |  4 +++-
 Documentation/devicetree/bindings/net/keystone-netcp.txt       | 10 +++++-----
 Documentation/devicetree/bindings/net/macb.txt                 |  5 ++---
 Documentation/devicetree/bindings/net/marvell-pxa168.txt       |  4 +++-
 Documentation/devicetree/bindings/net/microchip,enc28j60.txt   |  3 ++-
 Documentation/devicetree/bindings/net/microchip,lan78xx.txt    |  5 ++---
 Documentation/devicetree/bindings/net/qca,qca7000.txt          |  4 +++-
 Documentation/devicetree/bindings/net/samsung-sxgbe.txt        |  4 +++-
 .../devicetree/bindings/net/snps,dwc-qos-ethernet.txt          |  5 +++--
 .../devicetree/bindings/net/socionext,uniphier-ave4.txt        |  4 ++--
 Documentation/devicetree/bindings/net/socionext-netsec.txt     |  5 +++--
 .../devicetree/bindings/net/wireless/mediatek,mt76.txt         |  5 +++--
 Documentation/devicetree/bindings/net/wireless/qca,ath9k.txt   |  4 ++--
 21 files changed, 58 insertions(+), 42 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/altera_tse.txt b/Documentation/devicetree/bindings/net/altera_tse.txt
index 0e21df9..0b7d4d3 100644
--- a/Documentation/devicetree/bindings/net/altera_tse.txt
+++ b/Documentation/devicetree/bindings/net/altera_tse.txt
@@ -46,9 +46,8 @@ Required properties:
 	- reg: phy id used to communicate to phy.
 	- device_type: Must be "ethernet-phy".
 
-Optional properties:
-- local-mac-address: See ethernet.txt in the same directory.
-- max-frame-size: See ethernet.txt in the same directory.
+The MAC address will be determined using the optional properties defined in
+ethernet.txt.
 
 Example:
 
diff --git a/Documentation/devicetree/bindings/net/amd-xgbe.txt b/Documentation/devicetree/bindings/net/amd-xgbe.txt
index 93dcb79..9c27dfc 100644
--- a/Documentation/devicetree/bindings/net/amd-xgbe.txt
+++ b/Documentation/devicetree/bindings/net/amd-xgbe.txt
@@ -24,8 +24,6 @@ Required properties:
 - phy-mode: See ethernet.txt file in the same directory
 
 Optional properties:
-- mac-address: mac address to be assigned to the device. Can be overridden
-  by UEFI.
 - dma-coherent: Present if dma operations are coherent
 - amd,per-channel-interrupt: Indicates that Rx and Tx complete will generate
   a unique interrupt for each DMA channel - this requires an additional
@@ -34,6 +32,9 @@ Optional properties:
     0 - 1GbE and 10GbE (default)
     1 - 2.5GbE and 10GbE
 
+The MAC address will be determined using the optional properties defined in
+ethernet.txt.
+
 The following optional properties are represented by an array with each
 value corresponding to a particular speed. The first array value represents
 the setting for the 1GbE speed, the second value for the 2.5GbE speed and
diff --git a/Documentation/devicetree/bindings/net/brcm,amac.txt b/Documentation/devicetree/bindings/net/brcm,amac.txt
index 0bfad65..0120ebe 100644
--- a/Documentation/devicetree/bindings/net/brcm,amac.txt
+++ b/Documentation/devicetree/bindings/net/brcm,amac.txt
@@ -16,8 +16,8 @@ Required properties:
 				registers (required for Northstar2)
  - interrupts:	Interrupt number
 
-Optional properties:
-- mac-address:	See ethernet.txt file in the same directory
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
 
 Examples:
 
diff --git a/Documentation/devicetree/bindings/net/cpsw.txt b/Documentation/devicetree/bindings/net/cpsw.txt
index 3264e19..7c7ac5e 100644
--- a/Documentation/devicetree/bindings/net/cpsw.txt
+++ b/Documentation/devicetree/bindings/net/cpsw.txt
@@ -49,10 +49,12 @@ Required properties:
 
 Optional properties:
 - dual_emac_res_vlan	: Specifies VID to be used to segregate the ports
-- mac-address		: See ethernet.txt file in the same directory
 - phy_id		: Specifies slave phy id (deprecated, use phy-handle)
 - phy-handle		: See ethernet.txt file in the same directory
 
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
+
 Slave sub-nodes:
 - fixed-link		: See fixed-link.txt file in the same directory
 
diff --git a/Documentation/devicetree/bindings/net/davinci_emac.txt b/Documentation/devicetree/bindings/net/davinci_emac.txt
index ca83dcc..5e3579e 100644
--- a/Documentation/devicetree/bindings/net/davinci_emac.txt
+++ b/Documentation/devicetree/bindings/net/davinci_emac.txt
@@ -20,11 +20,12 @@ Required properties:
 Optional properties:
 - phy-handle: See ethernet.txt file in the same directory.
               If absent, davinci_emac driver defaults to 100/FULL.
-- nvmem-cells: phandle, reference to an nvmem node for the MAC address
-- nvmem-cell-names: string, should be "mac-address" if nvmem is to be used
 - ti,davinci-rmii-en: 1 byte, 1 means use RMII
 - ti,davinci-no-bd-ram: boolean, does EMAC have BD RAM?
 
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
+
 Example (enbw_cmc board):
 	eth0: emac@1e20000 {
 		compatible = "ti,davinci-dm6467-emac";
diff --git a/Documentation/devicetree/bindings/net/dsa/dsa.txt b/Documentation/devicetree/bindings/net/dsa/dsa.txt
index d66a529..a237567 100644
--- a/Documentation/devicetree/bindings/net/dsa/dsa.txt
+++ b/Documentation/devicetree/bindings/net/dsa/dsa.txt
@@ -71,9 +71,8 @@ properties, described in binding documents:
 			  Documentation/devicetree/bindings/net/fixed-link.txt
 			  for details.
 
-- local-mac-address	: See
-			  Documentation/devicetree/bindings/net/ethernet.txt
-			  for details.
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
 
 Example
 
diff --git a/Documentation/devicetree/bindings/net/ethernet.txt b/Documentation/devicetree/bindings/net/ethernet.txt
index a686215..6992444 100644
--- a/Documentation/devicetree/bindings/net/ethernet.txt
+++ b/Documentation/devicetree/bindings/net/ethernet.txt
@@ -4,12 +4,14 @@ NOTE: All 'phy*' properties documented below are Ethernet specific. For the
 generic PHY 'phys' property, see
 Documentation/devicetree/bindings/phy/phy-bindings.txt.
 
-- local-mac-address: array of 6 bytes, specifies the MAC address that was
-  assigned to the network device;
 - mac-address: array of 6 bytes, specifies the MAC address that was last used by
   the boot program; should be used in cases where the MAC address assigned to
   the device by the boot program is different from the "local-mac-address"
   property;
+- local-mac-address: array of 6 bytes, specifies the MAC address that was
+  assigned to the network device;
+- nvmem-cells: phandle, reference to an nvmem node for the MAC address
+- nvmem-cell-names: string, should be "mac-address" if nvmem is to be used
 - max-speed: number, specifies maximum speed in Mbit/s supported by the device;
 - max-frame-size: number, maximum transfer unit (IEEE defined MTU), rather than
   the maximum frame size (there's contradiction in the Devicetree
diff --git a/Documentation/devicetree/bindings/net/hisilicon-femac.txt b/Documentation/devicetree/bindings/net/hisilicon-femac.txt
index d11af5e..5f96976 100644
--- a/Documentation/devicetree/bindings/net/hisilicon-femac.txt
+++ b/Documentation/devicetree/bindings/net/hisilicon-femac.txt
@@ -14,7 +14,6 @@ Required properties:
 	the PHY reset signal(optional).
 - reset-names: should contain the reset signal name "mac"(required)
 	and "phy"(optional).
-- mac-address: see ethernet.txt [1].
 - phy-mode: see ethernet.txt [1].
 - phy-handle: see ethernet.txt [1].
 - hisilicon,phy-reset-delays-us: triplet of delays if PHY reset signal given.
@@ -22,6 +21,9 @@ Required properties:
 	The 2nd cell is reset pulse in micro seconds.
 	The 3rd cell is reset post-delay in micro seconds.
 
+The MAC address will be determined using the optional properties
+defined in ethernet.txt[1].
+
 [1] Documentation/devicetree/bindings/net/ethernet.txt
 
 Example:
diff --git a/Documentation/devicetree/bindings/net/hisilicon-hix5hd2-gmac.txt b/Documentation/devicetree/bindings/net/hisilicon-hix5hd2-gmac.txt
index eea73ad..cddf46b 100644
--- a/Documentation/devicetree/bindings/net/hisilicon-hix5hd2-gmac.txt
+++ b/Documentation/devicetree/bindings/net/hisilicon-hix5hd2-gmac.txt
@@ -18,7 +18,6 @@ Required properties:
 - #size-cells: must be <0>.
 - phy-mode: see ethernet.txt [1].
 - phy-handle: see ethernet.txt [1].
-- mac-address: see ethernet.txt [1].
 - clocks: clock phandle and specifier pair.
 - clock-names: contain the clock name "mac_core"(required) and "mac_ifc"(optional).
 - resets: should contain the phandle to the MAC core reset signal(optional),
@@ -31,6 +30,9 @@ Required properties:
 	The 2nd cell is reset pulse in micro seconds.
 	The 3rd cell is reset post-delay in micro seconds.
 
+The MAC address will be determined using the properties defined in
+ethernet.txt[1].
+
 - PHY subnode: inherits from phy binding [2]
 
 [1] Documentation/devicetree/bindings/net/ethernet.txt
diff --git a/Documentation/devicetree/bindings/net/keystone-netcp.txt b/Documentation/devicetree/bindings/net/keystone-netcp.txt
index 04ba1dc..3a65aab 100644
--- a/Documentation/devicetree/bindings/net/keystone-netcp.txt
+++ b/Documentation/devicetree/bindings/net/keystone-netcp.txt
@@ -135,14 +135,14 @@ Optional properties:
 		are swapped.  The netcp driver will swap the two DWORDs
 		back to the proper order when this property is set to 2
 		when it obtains the mac address from efuse.
-- local-mac-address:	the driver is designed to use the of_get_mac_address api
-			only if efuse-mac is 0. When efuse-mac is 0, the MAC
-			address is obtained from local-mac-address. If this
-			attribute is not present, then the driver will use a
-			random MAC address.
 - "netcp-device label":	phandle to the device specification for each of NetCP
 			sub-module attached to this interface.
 
+The MAC address will be determined using the optional properties defined in
+ethernet.txt, as provided by the of_get_mac_address API and only if efuse-mac
+is set to 0. If any of the optional MAC address properties are not present,
+then the driver will use random MAC address.
+
 Example binding:
 
 netcp: netcp@2000000 {
diff --git a/Documentation/devicetree/bindings/net/macb.txt b/Documentation/devicetree/bindings/net/macb.txt
index 8b80515..9c5e944 100644
--- a/Documentation/devicetree/bindings/net/macb.txt
+++ b/Documentation/devicetree/bindings/net/macb.txt
@@ -26,9 +26,8 @@ Required properties:
 	Optional elements: 'tsu_clk'
 - clocks: Phandles to input clocks.
 
-Optional properties:
-- nvmem-cells: phandle, reference to an nvmem node for the MAC address
-- nvmem-cell-names: string, should be "mac-address" if nvmem is to be used
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
 
 Optional properties for PHY child node:
 - reset-gpios : Should specify the gpio for phy reset
diff --git a/Documentation/devicetree/bindings/net/marvell-pxa168.txt b/Documentation/devicetree/bindings/net/marvell-pxa168.txt
index 845a148..5574af3 100644
--- a/Documentation/devicetree/bindings/net/marvell-pxa168.txt
+++ b/Documentation/devicetree/bindings/net/marvell-pxa168.txt
@@ -11,7 +11,9 @@ Optional properties:
 - #address-cells: must be 1 when using sub-nodes.
 - #size-cells: must be 0 when using sub-nodes.
 - phy-handle: see ethernet.txt file in the same directory.
-- local-mac-address: see ethernet.txt file in the same directory.
+
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
 
 Sub-nodes:
 Each PHY can be represented as a sub-node. This is not mandatory.
diff --git a/Documentation/devicetree/bindings/net/microchip,enc28j60.txt b/Documentation/devicetree/bindings/net/microchip,enc28j60.txt
index 24626e0..a827592 100644
--- a/Documentation/devicetree/bindings/net/microchip,enc28j60.txt
+++ b/Documentation/devicetree/bindings/net/microchip,enc28j60.txt
@@ -21,8 +21,9 @@ Optional properties:
 - spi-max-frequency: Maximum frequency of the SPI bus when accessing the ENC28J60.
   According to the ENC28J80 datasheet, the chip allows a maximum of 20 MHz, however,
   board designs may need to limit this value.
-- local-mac-address: See ethernet.txt in the same directory.
 
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
 
 Example (for NXP i.MX28 with pin control stuff for GPIO irq):
 
diff --git a/Documentation/devicetree/bindings/net/microchip,lan78xx.txt b/Documentation/devicetree/bindings/net/microchip,lan78xx.txt
index 76786a0..11a6795 100644
--- a/Documentation/devicetree/bindings/net/microchip,lan78xx.txt
+++ b/Documentation/devicetree/bindings/net/microchip,lan78xx.txt
@@ -7,9 +7,8 @@ The Device Tree properties, if present, override the OTP and EEPROM.
 Required properties:
 - compatible: Should be one of "usb424,7800", "usb424,7801" or "usb424,7850".
 
-Optional properties:
-- local-mac-address:   see ethernet.txt
-- mac-address:         see ethernet.txt
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
 
 Optional properties of the embedded PHY:
 - microchip,led-modes: a 0..4 element vector, with each element configuring
diff --git a/Documentation/devicetree/bindings/net/qca,qca7000.txt b/Documentation/devicetree/bindings/net/qca,qca7000.txt
index e4a8a51..21c36e5 100644
--- a/Documentation/devicetree/bindings/net/qca,qca7000.txt
+++ b/Documentation/devicetree/bindings/net/qca,qca7000.txt
@@ -23,7 +23,6 @@ Optional properties:
 		      Numbers smaller than 1000000 or greater than 16000000
 		      are invalid. Missing the property will set the SPI
 		      frequency to 8000000 Hertz.
-- local-mac-address : see ./ethernet.txt
 - qca,legacy-mode   : Set the SPI data transfer of the QCA7000 to legacy mode.
 		      In this mode the SPI master must toggle the chip select
 		      between each data word. In burst mode these gaps aren't
@@ -31,6 +30,9 @@ Optional properties:
 		      the QCA7000 is setup via GPIO pin strapping. If the
 		      property is missing the driver defaults to burst mode.
 
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
+
 SPI Example:
 
 /* Freescale i.MX28 SPI master*/
diff --git a/Documentation/devicetree/bindings/net/samsung-sxgbe.txt b/Documentation/devicetree/bindings/net/samsung-sxgbe.txt
index 46e5911..2cff6d8 100644
--- a/Documentation/devicetree/bindings/net/samsung-sxgbe.txt
+++ b/Documentation/devicetree/bindings/net/samsung-sxgbe.txt
@@ -21,10 +21,12 @@ Required properties:
   range.
 
 Optional properties:
-- mac-address: 6 bytes, mac address
 - max-frame-size: Maximum Transfer Unit (IEEE defined MTU), rather
 		  than the maximum frame size.
 
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
+
 Example:
 
 	aliases {
diff --git a/Documentation/devicetree/bindings/net/snps,dwc-qos-ethernet.txt b/Documentation/devicetree/bindings/net/snps,dwc-qos-ethernet.txt
index 36f1aef..ad3c6e1 100644
--- a/Documentation/devicetree/bindings/net/snps,dwc-qos-ethernet.txt
+++ b/Documentation/devicetree/bindings/net/snps,dwc-qos-ethernet.txt
@@ -103,8 +103,6 @@ Required properties:
 
 Optional properties:
 - dma-coherent: Present if dma operations are coherent
-- mac-address: See ethernet.txt in the same directory
-- local-mac-address: See ethernet.txt in the same directory
 - phy-reset-gpios: Phandle and specifier for any GPIO used to reset the PHY.
   See ../gpio/gpio.txt.
 - snps,en-lpi: If present it enables use of the AXI low-power interface
@@ -133,6 +131,9 @@ Optional properties:
     - device_type: Must be "ethernet-phy".
     - fixed-mode device tree subnode: see fixed-link.txt in the same directory
 
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
+
 Examples:
 ethernet2@40010000 {
 	clock-names = "phy_ref_clk", "apb_pclk";
diff --git a/Documentation/devicetree/bindings/net/socionext,uniphier-ave4.txt b/Documentation/devicetree/bindings/net/socionext,uniphier-ave4.txt
index fc8f017..4e85fc4 100644
--- a/Documentation/devicetree/bindings/net/socionext,uniphier-ave4.txt
+++ b/Documentation/devicetree/bindings/net/socionext,uniphier-ave4.txt
@@ -31,8 +31,8 @@ Required properties:
  - socionext,syscon-phy-mode: A phandle to syscon with one argument
 	that configures phy mode. The argument is the ID of MAC instance.
 
-Optional properties:
- - local-mac-address: See ethernet.txt in the same directory.
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
 
 Required subnode:
  - mdio: A container for child nodes representing phy nodes.
diff --git a/Documentation/devicetree/bindings/net/socionext-netsec.txt b/Documentation/devicetree/bindings/net/socionext-netsec.txt
index 0cff94f..9d6c9feb 100644
--- a/Documentation/devicetree/bindings/net/socionext-netsec.txt
+++ b/Documentation/devicetree/bindings/net/socionext-netsec.txt
@@ -26,11 +26,12 @@ Required properties:
 Optional properties: (See ethernet.txt file in the same directory)
 - dma-coherent: Boolean property, must only be present if memory
 	accesses performed by the device are cache coherent.
-- local-mac-address: See ethernet.txt in the same directory.
-- mac-address: See ethernet.txt in the same directory.
 - max-speed: See ethernet.txt in the same directory.
 - max-frame-size: See ethernet.txt in the same directory.
 
+The MAC address will be determined using the optional properties
+defined in ethernet.txt.
+
 Example:
 	eth0: ethernet@522d0000 {
 		compatible = "socionext,synquacer-netsec";
diff --git a/Documentation/devicetree/bindings/net/wireless/mediatek,mt76.txt b/Documentation/devicetree/bindings/net/wireless/mediatek,mt76.txt
index 7b9a776..7466550 100644
--- a/Documentation/devicetree/bindings/net/wireless/mediatek,mt76.txt
+++ b/Documentation/devicetree/bindings/net/wireless/mediatek,mt76.txt
@@ -13,11 +13,12 @@ properties:
 
 Optional properties:
 
-- mac-address: See ethernet.txt in the parent directory
-- local-mac-address: See ethernet.txt in the parent directory
 - ieee80211-freq-limit: See ieee80211.txt
 - mediatek,mtd-eeprom: Specify a MTD partition + offset containing EEPROM data
 
+The driver is using of_get_mac_address API, so the MAC address can be as well
+be set with corresponding optional properties defined in net/ethernet.txt.
+
 Optional nodes:
 - led: Properties for a connected LED
   Optional properties:
diff --git a/Documentation/devicetree/bindings/net/wireless/qca,ath9k.txt b/Documentation/devicetree/bindings/net/wireless/qca,ath9k.txt
index b7396c8..aaaeeb5 100644
--- a/Documentation/devicetree/bindings/net/wireless/qca,ath9k.txt
+++ b/Documentation/devicetree/bindings/net/wireless/qca,ath9k.txt
@@ -34,9 +34,9 @@ Optional properties:
 			ath9k wireless chip (in this case the calibration /
 			EEPROM data will be loaded from userspace using the
 			kernel firmware loader).
-- mac-address: See ethernet.txt in the parent directory
-- local-mac-address: See ethernet.txt in the parent directory
 
+The MAC address will be determined using the optional properties defined in
+net/ethernet.txt.
 
 In this example, the node is defined as child node of the PCI controller:
 &pci0 {
-- 
1.9.1

[PATCH v3 03/10] net: macb: support of_get_mac_address new ERR_PTR error

[Petr Štetiar]

There was NVMEM support added directly to of_get_mac_address, and it
uses nvmem_get_mac_address under the hood, so we can remove it. As
of_get_mac_address can now return NULL and ERR_PTR encoded error values,
adjust to that as well.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---

 Changes since v2:

 * ERR_PTR and EPROBE_DEFER handling

 drivers/net/ethernet/cadence/macb_main.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 3da2795..964911a 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -4172,15 +4172,13 @@ static int macb_probe(struct platform_device *pdev)
 		bp->rx_intr_mask |= MACB_BIT(RXUBR);
 
 	mac = of_get_mac_address(np);
-	if (mac) {
+	if (PTR_ERR(mac) == -EPROBE_DEFER) {
+		err = -EPROBE_DEFER;
+		goto err_out_free_netdev;
+	} else if (!IS_ERR_OR_NULL(mac)) {
 		ether_addr_copy(bp->dev->dev_addr, mac);
 	} else {
-		err = nvmem_get_mac_address(&pdev->dev, bp->dev->dev_addr);
-		if (err) {
-			if (err == -EPROBE_DEFER)
-				goto err_out_free_netdev;
-			macb_get_hwaddr(bp);
-		}
+		macb_get_hwaddr(bp);
 	}
 
 	err = of_get_phy_mode(np);
-- 
1.9.1

[PATCH v3 04/10] net: davinci: support of_get_mac_address new ERR_PTR error

[Petr Štetiar]

There was NVMEM support added directly to of_get_mac_address, and it
uses nvmem_get_mac_address under the hood, so we can remove it. As
of_get_mac_address can now return NULL and ERR_PTR encoded error values,
adjust to that as well.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---

 Changes since v2:

 * ERR_PTR handling

 drivers/net/ethernet/ti/davinci_emac.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/ti/davinci_emac.c b/drivers/net/ethernet/ti/davinci_emac.c
index 57450b1..4229ef0 100644
--- a/drivers/net/ethernet/ti/davinci_emac.c
+++ b/drivers/net/ethernet/ti/davinci_emac.c
@@ -1714,7 +1714,7 @@ static struct net_device_stats *emac_dev_getnetstats(struct net_device *ndev)
 
 	if (!is_valid_ether_addr(pdata->mac_addr)) {
 		mac_addr = of_get_mac_address(np);
-		if (mac_addr)
+		if (!IS_ERR_OR_NULL(mac_addr))
 			ether_addr_copy(pdata->mac_addr, mac_addr);
 	}
 
@@ -1912,15 +1912,11 @@ static int davinci_emac_probe(struct platform_device *pdev)
 		ether_addr_copy(ndev->dev_addr, priv->mac_addr);
 
 	if (!is_valid_ether_addr(priv->mac_addr)) {
-		/* Try nvmem if MAC wasn't passed over pdata or DT. */
-		rc = nvmem_get_mac_address(&pdev->dev, priv->mac_addr);
-		if (rc) {
-			/* Use random MAC if still none obtained. */
-			eth_hw_addr_random(ndev);
-			memcpy(priv->mac_addr, ndev->dev_addr, ndev->addr_len);
-			dev_warn(&pdev->dev, "using random MAC addr: %pM\n",
-				 priv->mac_addr);
-		}
+		/* Use random MAC if still none obtained. */
+		eth_hw_addr_random(ndev);
+		memcpy(priv->mac_addr, ndev->dev_addr, ndev->addr_len);
+		dev_warn(&pdev->dev, "using random MAC addr: %pM\n",
+			 priv->mac_addr);
 	}
 
 	ndev->netdev_ops = &emac_netdev_ops;
-- 
1.9.1

[PATCH v3 05/10] net: ethernet: support of_get_mac_address new ERR_PTR error

[Petr Štetiar]

There was NVMEM support added to of_get_mac_address, so it could now
return NULL and ERR_PTR encoded error values, so we need to adjust all
current users of of_get_mac_address to this new fact.

While at it, remove superfluous is_valid_ether_addr as the MAC address
returned from of_get_mac_address is always valid and checked by
is_valid_ether_addr anyway.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---
 drivers/net/ethernet/aeroflex/greth.c                 | 2 +-
 drivers/net/ethernet/allwinner/sun4i-emac.c           | 2 +-
 drivers/net/ethernet/altera/altera_tse_main.c         | 2 +-
 drivers/net/ethernet/arc/emac_main.c                  | 2 +-
 drivers/net/ethernet/aurora/nb8800.c                  | 2 +-
 drivers/net/ethernet/broadcom/bcmsysport.c            | 2 +-
 drivers/net/ethernet/broadcom/bgmac-bcma.c            | 2 +-
 drivers/net/ethernet/broadcom/bgmac-platform.c        | 2 +-
 drivers/net/ethernet/broadcom/genet/bcmgenet.c        | 2 +-
 drivers/net/ethernet/cavium/octeon/octeon_mgmt.c      | 2 +-
 drivers/net/ethernet/cavium/thunder/thunder_bgx.c     | 2 +-
 drivers/net/ethernet/davicom/dm9000.c                 | 2 +-
 drivers/net/ethernet/ethoc.c                          | 2 +-
 drivers/net/ethernet/ezchip/nps_enet.c                | 2 +-
 drivers/net/ethernet/freescale/fec_main.c             | 2 +-
 drivers/net/ethernet/freescale/fec_mpc52xx.c          | 2 +-
 drivers/net/ethernet/freescale/fman/mac.c             | 2 +-
 drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c | 2 +-
 drivers/net/ethernet/freescale/gianfar.c              | 2 +-
 drivers/net/ethernet/freescale/ucc_geth.c             | 2 +-
 drivers/net/ethernet/hisilicon/hisi_femac.c           | 2 +-
 drivers/net/ethernet/hisilicon/hix5hd2_gmac.c         | 2 +-
 drivers/net/ethernet/lantiq_xrx200.c                  | 2 +-
 drivers/net/ethernet/marvell/mv643xx_eth.c            | 2 +-
 drivers/net/ethernet/marvell/mvneta.c                 | 2 +-
 drivers/net/ethernet/marvell/pxa168_eth.c             | 2 +-
 drivers/net/ethernet/marvell/sky2.c                   | 2 +-
 drivers/net/ethernet/mediatek/mtk_eth_soc.c           | 2 +-
 drivers/net/ethernet/micrel/ks8851.c                  | 2 +-
 drivers/net/ethernet/micrel/ks8851_mll.c              | 2 +-
 drivers/net/ethernet/microchip/enc28j60.c             | 2 +-
 drivers/net/ethernet/nxp/lpc_eth.c                    | 2 +-
 drivers/net/ethernet/qualcomm/qca_spi.c               | 2 +-
 drivers/net/ethernet/qualcomm/qca_uart.c              | 2 +-
 drivers/net/ethernet/renesas/ravb_main.c              | 2 +-
 drivers/net/ethernet/renesas/sh_eth.c                 | 2 +-
 drivers/net/ethernet/samsung/sxgbe/sxgbe_platform.c   | 2 +-
 drivers/net/ethernet/socionext/sni_ave.c              | 2 +-
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c     | 2 +-
 drivers/net/ethernet/ti/cpsw.c                        | 2 +-
 drivers/net/ethernet/ti/netcp_core.c                  | 2 +-
 drivers/net/ethernet/wiznet/w5100.c                   | 2 +-
 drivers/net/ethernet/xilinx/ll_temac_main.c           | 2 +-
 drivers/net/ethernet/xilinx/xilinx_axienet_main.c     | 2 +-
 drivers/net/ethernet/xilinx/xilinx_emaclite.c         | 2 +-
 net/ethernet/eth.c                                    | 2 +-
 46 files changed, 46 insertions(+), 46 deletions(-)

diff --git a/drivers/net/ethernet/aeroflex/greth.c b/drivers/net/ethernet/aeroflex/greth.c
index 47e5984..ce4d2a5 100644
--- a/drivers/net/ethernet/aeroflex/greth.c
+++ b/drivers/net/ethernet/aeroflex/greth.c
@@ -1459,7 +1459,7 @@ static int greth_of_probe(struct platform_device *ofdev)
 		const u8 *addr;
 
 		addr = of_get_mac_address(ofdev->dev.of_node);
-		if (addr) {
+		if (!IS_ERR_OR_NULL(addr)) {
 			for (i = 0; i < 6; i++)
 				macaddr[i] = (unsigned int) addr[i];
 		} else {
diff --git a/drivers/net/ethernet/allwinner/sun4i-emac.c b/drivers/net/ethernet/allwinner/sun4i-emac.c
index e1acafa..9708199 100644
--- a/drivers/net/ethernet/allwinner/sun4i-emac.c
+++ b/drivers/net/ethernet/allwinner/sun4i-emac.c
@@ -870,7 +870,7 @@ static int emac_probe(struct platform_device *pdev)
 
 	/* Read MAC-address from DT */
 	mac_addr = of_get_mac_address(np);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
 
 	/* Check if the MAC address is valid, if not get a random one */
diff --git a/drivers/net/ethernet/altera/altera_tse_main.c b/drivers/net/ethernet/altera/altera_tse_main.c
index aa1d1f5..99a5149 100644
--- a/drivers/net/ethernet/altera/altera_tse_main.c
+++ b/drivers/net/ethernet/altera/altera_tse_main.c
@@ -1537,7 +1537,7 @@ static int altera_tse_probe(struct platform_device *pdev)
 
 	/* get default MAC address from device tree */
 	macaddr = of_get_mac_address(pdev->dev.of_node);
-	if (macaddr)
+	if (!IS_ERR_OR_NULL(macaddr))
 		ether_addr_copy(ndev->dev_addr, macaddr);
 	else
 		eth_hw_addr_random(ndev);
diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c
index ff3d685..b4bf803 100644
--- a/drivers/net/ethernet/arc/emac_main.c
+++ b/drivers/net/ethernet/arc/emac_main.c
@@ -960,7 +960,7 @@ int arc_emac_probe(struct net_device *ndev, int interface)
 	/* Get MAC address from device tree */
 	mac_addr = of_get_mac_address(dev->of_node);
 
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
 	else
 		eth_hw_addr_random(ndev);
diff --git a/drivers/net/ethernet/aurora/nb8800.c b/drivers/net/ethernet/aurora/nb8800.c
index 6f56276..30af865 100644
--- a/drivers/net/ethernet/aurora/nb8800.c
+++ b/drivers/net/ethernet/aurora/nb8800.c
@@ -1461,7 +1461,7 @@ static int nb8800_probe(struct platform_device *pdev)
 	dev->irq = irq;
 
 	mac = of_get_mac_address(pdev->dev.of_node);
-	if (mac)
+	if (!IS_ERR_OR_NULL(mac))
 		ether_addr_copy(dev->dev_addr, mac);
 
 	if (!is_valid_ether_addr(dev->dev_addr))
diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
index bc3ac36..c0a8c3c 100644
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -2548,7 +2548,7 @@ static int bcm_sysport_probe(struct platform_device *pdev)
 
 	/* Initialize netdevice members */
 	macaddr = of_get_mac_address(dn);
-	if (!macaddr || !is_valid_ether_addr(macaddr)) {
+	if (IS_ERR_OR_NULL(macaddr)) {
 		dev_warn(&pdev->dev, "using random Ethernet MAC\n");
 		eth_hw_addr_random(dev);
 	} else {
diff --git a/drivers/net/ethernet/broadcom/bgmac-bcma.c b/drivers/net/ethernet/broadcom/bgmac-bcma.c
index 6fe074c..34d1830 100644
--- a/drivers/net/ethernet/broadcom/bgmac-bcma.c
+++ b/drivers/net/ethernet/broadcom/bgmac-bcma.c
@@ -132,7 +132,7 @@ static int bgmac_probe(struct bcma_device *core)
 		mac = of_get_mac_address(bgmac->dev->of_node);
 
 	/* If no MAC address assigned via device tree, check SPROM */
-	if (!mac) {
+	if (IS_ERR_OR_NULL(mac)) {
 		switch (core->core_unit) {
 		case 0:
 			mac = sprom->et0mac;
diff --git a/drivers/net/ethernet/broadcom/bgmac-platform.c b/drivers/net/ethernet/broadcom/bgmac-platform.c
index 894eda5..2cd7387 100644
--- a/drivers/net/ethernet/broadcom/bgmac-platform.c
+++ b/drivers/net/ethernet/broadcom/bgmac-platform.c
@@ -193,7 +193,7 @@ static int bgmac_probe(struct platform_device *pdev)
 	bgmac->dma_dev = &pdev->dev;
 
 	mac_addr = of_get_mac_address(np);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		ether_addr_copy(bgmac->net_dev->dev_addr, mac_addr);
 	else
 		dev_warn(&pdev->dev, "MAC address not present in device tree\n");
diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index 983245c..8f45c6b 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -3476,7 +3476,7 @@ static int bcmgenet_probe(struct platform_device *pdev)
 
 	if (dn) {
 		macaddr = of_get_mac_address(dn);
-		if (!macaddr) {
+		if (IS_ERR_OR_NULL(macaddr)) {
 			dev_err(&pdev->dev, "can't find MAC address\n");
 			err = -EINVAL;
 			goto err;
diff --git a/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c b/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
index 5359c10..5bc2d61 100644
--- a/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
+++ b/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
@@ -1503,7 +1503,7 @@ static int octeon_mgmt_probe(struct platform_device *pdev)
 
 	mac = of_get_mac_address(pdev->dev.of_node);
 
-	if (mac)
+	if (!IS_ERR_OR_NULL(mac))
 		memcpy(netdev->dev_addr, mac, ETH_ALEN);
 	else
 		eth_hw_addr_random(netdev);
diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
index 673c57b..d29ece0 100644
--- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
+++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
@@ -1484,7 +1484,7 @@ static int bgx_init_of_phy(struct bgx *bgx)
 			break;
 
 		mac = of_get_mac_address(node);
-		if (mac)
+		if (!IS_ERR_OR_NULL(mac))
 			ether_addr_copy(bgx->lmac[lmac].mac, mac);
 
 		SET_NETDEV_DEV(&bgx->lmac[lmac].netdev, &bgx->pdev->dev);
diff --git a/drivers/net/ethernet/davicom/dm9000.c b/drivers/net/ethernet/davicom/dm9000.c
index c2586f4..30945da 100644
--- a/drivers/net/ethernet/davicom/dm9000.c
+++ b/drivers/net/ethernet/davicom/dm9000.c
@@ -1412,7 +1412,7 @@ static struct dm9000_plat_data *dm9000_parse_dt(struct device *dev)
 		pdata->flags |= DM9000_PLATF_NO_EEPROM;
 
 	mac_addr = of_get_mac_address(np);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		memcpy(pdata->dev_addr, mac_addr, sizeof(pdata->dev_addr));
 
 	return pdata;
diff --git a/drivers/net/ethernet/ethoc.c b/drivers/net/ethernet/ethoc.c
index 0f3e7f2..eaf9377 100644
--- a/drivers/net/ethernet/ethoc.c
+++ b/drivers/net/ethernet/ethoc.c
@@ -1153,7 +1153,7 @@ static int ethoc_probe(struct platform_device *pdev)
 		const void *mac;
 
 		mac = of_get_mac_address(pdev->dev.of_node);
-		if (mac)
+		if (!IS_ERR_OR_NULL(mac))
 			ether_addr_copy(netdev->dev_addr, mac);
 		priv->phy_id = -1;
 	}
diff --git a/drivers/net/ethernet/ezchip/nps_enet.c b/drivers/net/ethernet/ezchip/nps_enet.c
index 659f1ad..5ab8c7e 100644
--- a/drivers/net/ethernet/ezchip/nps_enet.c
+++ b/drivers/net/ethernet/ezchip/nps_enet.c
@@ -616,7 +616,7 @@ static s32 nps_enet_probe(struct platform_device *pdev)
 
 	/* set kernel MAC address to dev */
 	mac_addr = of_get_mac_address(dev->of_node);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		ether_addr_copy(ndev->dev_addr, mac_addr);
 	else
 		eth_hw_addr_random(ndev);
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index a96ad20..145c611 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -1655,7 +1655,7 @@ static void fec_get_mac(struct net_device *ndev)
 		struct device_node *np = fep->pdev->dev.of_node;
 		if (np) {
 			const char *mac = of_get_mac_address(np);
-			if (mac)
+			if (!IS_ERR_OR_NULL(mac))
 				iap = (unsigned char *) mac;
 		}
 	}
diff --git a/drivers/net/ethernet/freescale/fec_mpc52xx.c b/drivers/net/ethernet/freescale/fec_mpc52xx.c
index c1968b3..3b323bb 100644
--- a/drivers/net/ethernet/freescale/fec_mpc52xx.c
+++ b/drivers/net/ethernet/freescale/fec_mpc52xx.c
@@ -902,7 +902,7 @@ static int mpc52xx_fec_probe(struct platform_device *op)
 	 * First try to read MAC address from DT
 	 */
 	mac_addr = of_get_mac_address(np);
-	if (mac_addr) {
+	if (!IS_ERR_OR_NULL(mac_addr)) {
 		memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
 	} else {
 		struct mpc52xx_fec __iomem *fec = priv->fec;
diff --git a/drivers/net/ethernet/freescale/fman/mac.c b/drivers/net/ethernet/freescale/fman/mac.c
index 3c21486..f7cfe40 100644
--- a/drivers/net/ethernet/freescale/fman/mac.c
+++ b/drivers/net/ethernet/freescale/fman/mac.c
@@ -724,7 +724,7 @@ static int mac_probe(struct platform_device *_of_dev)
 
 	/* Get the MAC address */
 	mac_addr = of_get_mac_address(mac_node);
-	if (!mac_addr) {
+	if (IS_ERR_OR_NULL(mac_addr)) {
 		dev_err(dev, "of_get_mac_address(%pOF) failed\n", mac_node);
 		err = -EINVAL;
 		goto _return_of_get_parent;
diff --git a/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c b/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
index 7c548ed..be70f9e 100644
--- a/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
+++ b/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
@@ -1014,7 +1014,7 @@ static int fs_enet_probe(struct platform_device *ofdev)
 	spin_lock_init(&fep->tx_lock);
 
 	mac_addr = of_get_mac_address(ofdev->dev.of_node);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
 
 	ret = fep->ops->allocate_bd(ndev);
diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c
index 45fcc96..7e33122 100644
--- a/drivers/net/ethernet/freescale/gianfar.c
+++ b/drivers/net/ethernet/freescale/gianfar.c
@@ -872,7 +872,7 @@ static int gfar_of_init(struct platform_device *ofdev, struct net_device **pdev)
 
 	mac_addr = of_get_mac_address(np);
 
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		memcpy(dev->dev_addr, mac_addr, ETH_ALEN);
 
 	if (model && !strcasecmp(model, "TSEC"))
diff --git a/drivers/net/ethernet/freescale/ucc_geth.c b/drivers/net/ethernet/freescale/ucc_geth.c
index eb3e65e..d125836 100644
--- a/drivers/net/ethernet/freescale/ucc_geth.c
+++ b/drivers/net/ethernet/freescale/ucc_geth.c
@@ -3910,7 +3910,7 @@ static int ucc_geth_probe(struct platform_device* ofdev)
 	}
 
 	mac_addr = of_get_mac_address(np);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		memcpy(dev->dev_addr, mac_addr, ETH_ALEN);
 
 	ugeth->ug_info = ug_info;
diff --git a/drivers/net/ethernet/hisilicon/hisi_femac.c b/drivers/net/ethernet/hisilicon/hisi_femac.c
index 2c28088..7e46dc9 100644
--- a/drivers/net/ethernet/hisilicon/hisi_femac.c
+++ b/drivers/net/ethernet/hisilicon/hisi_femac.c
@@ -870,7 +870,7 @@ static int hisi_femac_drv_probe(struct platform_device *pdev)
 			   phy_modes(phy->interface));
 
 	mac_addr = of_get_mac_address(node);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		ether_addr_copy(ndev->dev_addr, mac_addr);
 	if (!is_valid_ether_addr(ndev->dev_addr)) {
 		eth_hw_addr_random(ndev);
diff --git a/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c b/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c
index e5d853b..ed4a3d2 100644
--- a/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c
+++ b/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c
@@ -1229,7 +1229,7 @@ static int hix5hd2_dev_probe(struct platform_device *pdev)
 	}
 
 	mac_addr = of_get_mac_address(node);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		ether_addr_copy(ndev->dev_addr, mac_addr);
 	if (!is_valid_ether_addr(ndev->dev_addr)) {
 		eth_hw_addr_random(ndev);
diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c
index d29104d..2308479 100644
--- a/drivers/net/ethernet/lantiq_xrx200.c
+++ b/drivers/net/ethernet/lantiq_xrx200.c
@@ -478,7 +478,7 @@ static int xrx200_probe(struct platform_device *pdev)
 	}
 
 	mac = of_get_mac_address(np);
-	if (mac && is_valid_ether_addr(mac))
+	if (!IS_ERR_OR_NULL(mac))
 		ether_addr_copy(net_dev->dev_addr, mac);
 	else
 		eth_hw_addr_random(net_dev);
diff --git a/drivers/net/ethernet/marvell/mv643xx_eth.c b/drivers/net/ethernet/marvell/mv643xx_eth.c
index 292a668..aa35f72 100644
--- a/drivers/net/ethernet/marvell/mv643xx_eth.c
+++ b/drivers/net/ethernet/marvell/mv643xx_eth.c
@@ -2749,7 +2749,7 @@ static int mv643xx_eth_shared_of_add_port(struct platform_device *pdev,
 	}
 
 	mac_addr = of_get_mac_address(pnp);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		memcpy(ppd.mac_addr, mac_addr, ETH_ALEN);
 
 	mv643xx_eth_property(pnp, "tx-queue-size", ppd.tx_queue_size);
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index c0a3718..117bcf4 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -4563,7 +4563,7 @@ static int mvneta_probe(struct platform_device *pdev)
 	}
 
 	dt_mac_addr = of_get_mac_address(dn);
-	if (dt_mac_addr) {
+	if (!IS_ERR_OR_NULL(dt_mac_addr)) {
 		mac_from = "device tree";
 		memcpy(dev->dev_addr, dt_mac_addr, ETH_ALEN);
 	} else {
diff --git a/drivers/net/ethernet/marvell/pxa168_eth.c b/drivers/net/ethernet/marvell/pxa168_eth.c
index 35f2142..ce037e8 100644
--- a/drivers/net/ethernet/marvell/pxa168_eth.c
+++ b/drivers/net/ethernet/marvell/pxa168_eth.c
@@ -1461,7 +1461,7 @@ static int pxa168_eth_probe(struct platform_device *pdev)
 	if (pdev->dev.of_node)
 		mac_addr = of_get_mac_address(pdev->dev.of_node);
 
-	if (mac_addr && is_valid_ether_addr(mac_addr)) {
+	if (!IS_ERR_OR_NULL(mac_addr)) {
 		ether_addr_copy(dev->dev_addr, mac_addr);
 	} else {
 		/* try reading the mac address, if set by the bootloader */
diff --git a/drivers/net/ethernet/marvell/sky2.c b/drivers/net/ethernet/marvell/sky2.c
index 8b3495e..821177f 100644
--- a/drivers/net/ethernet/marvell/sky2.c
+++ b/drivers/net/ethernet/marvell/sky2.c
@@ -4808,7 +4808,7 @@ static struct net_device *sky2_init_netdev(struct sky2_hw *hw, unsigned port,
 	 * 2) from internal registers set by bootloader
 	 */
 	iap = of_get_mac_address(hw->pdev->dev.of_node);
-	if (iap)
+	if (!IS_ERR_OR_NULL(iap))
 		memcpy(dev->dev_addr, iap, ETH_ALEN);
 	else
 		memcpy_fromio(dev->dev_addr, hw->regs + B2_MAC_1 + port * 8,
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 549d364..03cb59a 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -2027,7 +2027,7 @@ static int __init mtk_init(struct net_device *dev)
 	const char *mac_addr;
 
 	mac_addr = of_get_mac_address(mac->of_node);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		ether_addr_copy(dev->dev_addr, mac_addr);
 
 	/* If the mac address is invalid, use random mac address  */
diff --git a/drivers/net/ethernet/micrel/ks8851.c b/drivers/net/ethernet/micrel/ks8851.c
index 7849119..b1b2896 100644
--- a/drivers/net/ethernet/micrel/ks8851.c
+++ b/drivers/net/ethernet/micrel/ks8851.c
@@ -425,7 +425,7 @@ static void ks8851_init_mac(struct ks8851_net *ks)
 	const u8 *mac_addr;
 
 	mac_addr = of_get_mac_address(ks->spidev->dev.of_node);
-	if (mac_addr) {
+	if (!IS_ERR_OR_NULL(mac_addr)) {
 		memcpy(dev->dev_addr, mac_addr, ETH_ALEN);
 		ks8851_write_mac_addr(dev);
 		return;
diff --git a/drivers/net/ethernet/micrel/ks8851_mll.c b/drivers/net/ethernet/micrel/ks8851_mll.c
index c946841..d44a094 100644
--- a/drivers/net/ethernet/micrel/ks8851_mll.c
+++ b/drivers/net/ethernet/micrel/ks8851_mll.c
@@ -1327,7 +1327,7 @@ static int ks8851_probe(struct platform_device *pdev)
 	/* overwriting the default MAC address */
 	if (pdev->dev.of_node) {
 		mac = of_get_mac_address(pdev->dev.of_node);
-		if (mac)
+		if (!IS_ERR_OR_NULL(mac))
 			memcpy(ks->mac_addr, mac, ETH_ALEN);
 	} else {
 		struct ks8851_mll_platform_data *pdata;
diff --git a/drivers/net/ethernet/microchip/enc28j60.c b/drivers/net/ethernet/microchip/enc28j60.c
index 8f72587..f8d5fd3 100644
--- a/drivers/net/ethernet/microchip/enc28j60.c
+++ b/drivers/net/ethernet/microchip/enc28j60.c
@@ -1588,7 +1588,7 @@ static int enc28j60_probe(struct spi_device *spi)
 	}
 
 	macaddr = of_get_mac_address(spi->dev.of_node);
-	if (macaddr)
+	if (!IS_ERR_OR_NULL(macaddr))
 		ether_addr_copy(dev->dev_addr, macaddr);
 	else
 		eth_hw_addr_random(dev);
diff --git a/drivers/net/ethernet/nxp/lpc_eth.c b/drivers/net/ethernet/nxp/lpc_eth.c
index 89d1739..336b6aa 100644
--- a/drivers/net/ethernet/nxp/lpc_eth.c
+++ b/drivers/net/ethernet/nxp/lpc_eth.c
@@ -1368,7 +1368,7 @@ static int lpc_eth_drv_probe(struct platform_device *pdev)
 
 	if (!is_valid_ether_addr(ndev->dev_addr)) {
 		const char *macaddr = of_get_mac_address(np);
-		if (macaddr)
+		if (!IS_ERR_OR_NULL(macaddr))
 			memcpy(ndev->dev_addr, macaddr, ETH_ALEN);
 	}
 	if (!is_valid_ether_addr(ndev->dev_addr))
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c
index 97f9295..def5192 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.c
+++ b/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -966,7 +966,7 @@
 
 	mac = of_get_mac_address(spi->dev.of_node);
 
-	if (mac)
+	if (!IS_ERR_OR_NULL(mac))
 		ether_addr_copy(qca->net_dev->dev_addr, mac);
 
 	if (!is_valid_ether_addr(qca->net_dev->dev_addr)) {
diff --git a/drivers/net/ethernet/qualcomm/qca_uart.c b/drivers/net/ethernet/qualcomm/qca_uart.c
index db6068c..ae78066 100644
--- a/drivers/net/ethernet/qualcomm/qca_uart.c
+++ b/drivers/net/ethernet/qualcomm/qca_uart.c
@@ -351,7 +351,7 @@ static int qca_uart_probe(struct serdev_device *serdev)
 
 	mac = of_get_mac_address(serdev->dev.of_node);
 
-	if (mac)
+	if (!IS_ERR_OR_NULL(mac))
 		ether_addr_copy(qca->net_dev->dev_addr, mac);
 
 	if (!is_valid_ether_addr(qca->net_dev->dev_addr)) {
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 8154b38..77e9b02 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -111,7 +111,7 @@ static void ravb_set_buffer_align(struct sk_buff *skb)
  */
 static void ravb_read_mac_address(struct net_device *ndev, const u8 *mac)
 {
-	if (mac) {
+	if (!IS_ERR_OR_NULL(mac)) {
 		ether_addr_copy(ndev->dev_addr, mac);
 	} else {
 		u32 mahr = ravb_read(ndev, MAHR);
diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index e33af37..e89ba82 100644
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -3193,7 +3193,7 @@ static struct sh_eth_plat_data *sh_eth_parse_dt(struct device *dev)
 	pdata->phy_interface = ret;
 
 	mac_addr = of_get_mac_address(np);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		memcpy(pdata->mac_addr, mac_addr, ETH_ALEN);
 
 	pdata->no_ether_link =
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_platform.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_platform.c
index fbd00cb..d2bc941 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_platform.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_platform.c
@@ -124,7 +124,7 @@ static int sxgbe_platform_probe(struct platform_device *pdev)
 	}
 
 	/* Get MAC address if available (DT) */
-	if (mac)
+	if (!IS_ERR_OR_NULL(mac))
 		ether_addr_copy(priv->dev->dev_addr, mac);
 
 	/* Get the TX/RX IRQ numbers */
diff --git a/drivers/net/ethernet/socionext/sni_ave.c b/drivers/net/ethernet/socionext/sni_ave.c
index bb6d5fb..4194ef7 100644
--- a/drivers/net/ethernet/socionext/sni_ave.c
+++ b/drivers/net/ethernet/socionext/sni_ave.c
@@ -1599,7 +1599,7 @@ static int ave_probe(struct platform_device *pdev)
 	ndev->max_mtu = AVE_MAX_ETHFRAME - (ETH_HLEN + ETH_FCS_LEN);
 
 	mac_addr = of_get_mac_address(np);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		ether_addr_copy(ndev->dev_addr, mac_addr);
 
 	/* if the mac address is invalid, use random mac address */
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 4871243..d3664e6 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -4262,7 +4262,7 @@ int stmmac_dvr_probe(struct device *device,
 	priv->wol_irq = res->wol_irq;
 	priv->lpi_irq = res->lpi_irq;
 
-	if (res->mac)
+	if (!IS_ERR_OR_NULL(res->mac))
 		memcpy(priv->dev->dev_addr, res->mac, ETH_ALEN);
 
 	dev_set_drvdata(device, priv->dev);
diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index a591583..6aaacaf 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -3344,7 +3344,7 @@ static int cpsw_probe_dt(struct cpsw_platform_data *data,
 
 no_phy_slave:
 		mac_addr = of_get_mac_address(slave_node);
-		if (mac_addr) {
+		if (!IS_ERR_OR_NULL(mac_addr)) {
 			memcpy(slave_data->mac_addr, mac_addr, ETH_ALEN);
 		} else {
 			ret = ti_cm_get_macid(&pdev->dev, i,
diff --git a/drivers/net/ethernet/ti/netcp_core.c b/drivers/net/ethernet/ti/netcp_core.c
index d847f67..c413637 100644
--- a/drivers/net/ethernet/ti/netcp_core.c
+++ b/drivers/net/ethernet/ti/netcp_core.c
@@ -2045,7 +2045,7 @@ static int netcp_create_interface(struct netcp_device *netcp_device,
 		devm_release_mem_region(dev, res.start, size);
 	} else {
 		mac_addr = of_get_mac_address(node_interface);
-		if (mac_addr)
+		if (!IS_ERR_OR_NULL(mac_addr))
 			ether_addr_copy(ndev->dev_addr, mac_addr);
 		else
 			eth_random_addr(ndev->dev_addr);
diff --git a/drivers/net/ethernet/wiznet/w5100.c b/drivers/net/ethernet/wiznet/w5100.c
index d8ba512..b0052933 100644
--- a/drivers/net/ethernet/wiznet/w5100.c
+++ b/drivers/net/ethernet/wiznet/w5100.c
@@ -1164,7 +1164,7 @@ int w5100_probe(struct device *dev, const struct w5100_ops *ops,
 	INIT_WORK(&priv->setrx_work, w5100_setrx_work);
 	INIT_WORK(&priv->restart_work, w5100_restart_work);
 
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
 	else
 		eth_hw_addr_random(ndev);
diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c
index 44efffb..937dca0 100644
--- a/drivers/net/ethernet/xilinx/ll_temac_main.c
+++ b/drivers/net/ethernet/xilinx/ll_temac_main.c
@@ -1077,7 +1077,7 @@ static int temac_of_probe(struct platform_device *op)
 
 	/* Retrieve the MAC address */
 	addr = of_get_mac_address(op->dev.of_node);
-	if (!addr) {
+	if (IS_ERR_OR_NULL(addr)) {
 		dev_err(&op->dev, "could not find MAC address\n");
 		rc = -ENODEV;
 		goto err_iounmap_2;
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
index 4041c75..55f9d1b 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -1596,7 +1596,7 @@ static int axienet_probe(struct platform_device *pdev)
 
 	/* Retrieve the MAC address */
 	mac_addr = of_get_mac_address(pdev->dev.of_node);
-	if (!mac_addr) {
+	if (IS_ERR_OR_NULL(mac_addr)) {
 		dev_err(&pdev->dev, "could not find MAC address\n");
 		goto free_netdev;
 	}
diff --git a/drivers/net/ethernet/xilinx/xilinx_emaclite.c b/drivers/net/ethernet/xilinx/xilinx_emaclite.c
index b03a417..b7c0058 100644
--- a/drivers/net/ethernet/xilinx/xilinx_emaclite.c
+++ b/drivers/net/ethernet/xilinx/xilinx_emaclite.c
@@ -1143,7 +1143,7 @@ static int xemaclite_of_probe(struct platform_device *ofdev)
 	lp->rx_ping_pong = get_bool(ofdev, "xlnx,rx-ping-pong");
 	mac_address = of_get_mac_address(ofdev->dev.of_node);
 
-	if (mac_address) {
+	if (!IS_ERR_OR_NULL(mac_address)) {
 		/* Set the MAC address. */
 		memcpy(ndev->dev_addr, mac_address, ETH_ALEN);
 	} else {
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index f7a3d7a..b8c126c 100644
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c
@@ -554,7 +554,7 @@ int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr)
 	addr = NULL;
 	if (dp)
 		addr = of_get_mac_address(dp);
-	if (!addr)
+	if (IS_ERR_OR_NULL(addr))
 		addr = arch_get_platform_mac_address();
 
 	if (!addr)
-- 
1.9.1

[PATCH v3 06/10] net: usb: support of_get_mac_address new ERR_PTR error

[Petr Štetiar]

There was NVMEM support added to of_get_mac_address, so it could now
return NULL and ERR_PTR encoded error values, so we need to adjust all
current users of of_get_mac_address to this new fact.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---
 drivers/net/usb/smsc75xx.c | 2 +-
 drivers/net/usb/smsc95xx.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c
index ec287c9..7acfa64 100644
--- a/drivers/net/usb/smsc75xx.c
+++ b/drivers/net/usb/smsc75xx.c
@@ -774,7 +774,7 @@ static void smsc75xx_init_mac_address(struct usbnet *dev)
 
 	/* maybe the boot loader passed the MAC address in devicetree */
 	mac_addr = of_get_mac_address(dev->udev->dev.of_node);
-	if (mac_addr) {
+	if (!IS_ERR_OR_NULL(mac_addr)) {
 		memcpy(dev->net->dev_addr, mac_addr, ETH_ALEN);
 		return;
 	}
diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index e3d08626..841699f 100644
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -917,7 +917,7 @@ static void smsc95xx_init_mac_address(struct usbnet *dev)
 
 	/* maybe the boot loader passed the MAC address in devicetree */
 	mac_addr = of_get_mac_address(dev->udev->dev.of_node);
-	if (mac_addr) {
+	if (!IS_ERR_OR_NULL(mac_addr)) {
 		memcpy(dev->net->dev_addr, mac_addr, ETH_ALEN);
 		return;
 	}
-- 
1.9.1

[PATCH v3 07/10] net: wireless: support of_get_mac_address new ERR_PTR error

[Petr Štetiar]

There was NVMEM support added to of_get_mac_address, so it could now
return NULL and ERR_PTR encoded error values, so we need to adjust all
current users of of_get_mac_address to this new fact.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---
 drivers/net/wireless/ath/ath9k/init.c          | 2 +-
 drivers/net/wireless/mediatek/mt76/eeprom.c    | 2 +-
 drivers/net/wireless/ralink/rt2x00/rt2x00dev.c | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index 98141b6..8be2da8 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -642,7 +642,7 @@ static int ath9k_of_init(struct ath_softc *sc)
 	}
 
 	mac = of_get_mac_address(np);
-	if (mac)
+	if (!IS_ERR_OR_NULL(mac))
 		ether_addr_copy(common->macaddr, mac);
 
 	return 0;
diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
index a1529920d..7cb16ba 100644
--- a/drivers/net/wireless/mediatek/mt76/eeprom.c
+++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
@@ -94,7 +94,7 @@
 		return;
 
 	mac = of_get_mac_address(np);
-	if (mac)
+	if (!IS_ERR_OR_NULL(mac))
 		memcpy(dev->macaddr, mac, ETH_ALEN);
 #endif
 
diff --git a/drivers/net/wireless/ralink/rt2x00/rt2x00dev.c b/drivers/net/wireless/ralink/rt2x00/rt2x00dev.c
index 357c094..ef52467 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00dev.c
@@ -1007,7 +1007,7 @@ void rt2x00lib_set_mac_address(struct rt2x00_dev *rt2x00dev, u8 *eeprom_mac_addr
 	const char *mac_addr;
 
 	mac_addr = of_get_mac_address(rt2x00dev->dev->of_node);
-	if (mac_addr)
+	if (!IS_ERR_OR_NULL(mac_addr))
 		ether_addr_copy(eeprom_mac_addr, mac_addr);
 
 	if (!is_valid_ether_addr(eeprom_mac_addr)) {
-- 
1.9.1

[PATCH v3 08/10] staging: octeon-ethernet: support of_get_mac_address new ERR_PTR error

[Petr Štetiar]

There was NVMEM support added to of_get_mac_address, so it could now
return NULL and ERR_PTR encoded error values, so we need to adjust all
current users of of_get_mac_address to this new fact.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---
 drivers/staging/octeon/ethernet.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/octeon/ethernet.c b/drivers/staging/octeon/ethernet.c
index 986db76..8847a11c2 100644
--- a/drivers/staging/octeon/ethernet.c
+++ b/drivers/staging/octeon/ethernet.c
@@ -421,7 +421,7 @@ int cvm_oct_common_init(struct net_device *dev)
 	if (priv->of_node)
 		mac = of_get_mac_address(priv->of_node);
 
-	if (mac)
+	if (!IS_ERR_OR_NULL(mac))
 		ether_addr_copy(dev->dev_addr, mac);
 	else
 		eth_hw_addr_random(dev);
-- 
1.9.1

Re: [PATCH v3 08/10] staging: octeon-ethernet: support of_get_mac_address new ERR_PTR error

[Dan Carpenter]

On Fri, May 03, 2019 at 09:56:05AM +0200, Petr Štetiar wrote:
> There was NVMEM support added to of_get_mac_address, so it could now
> return NULL and ERR_PTR encoded error values, so we need to adjust all
> current users of of_get_mac_address to this new fact.

Which commit added NVMEM support?  It hasn't hit net-next or linux-next
yet...  Very strange.

Why would of_get_mac_address() return a mix of NULL and error pointers?
In that situation, then NULL is a special kind of success like when you
request feature and the feature works but it's disabled by the user.  We
don't want to treat it as an error but we still can't return a pointer
to a feature we don't have...  It's hard for me to imagine how that
makes sense for getting a mac address.

At the very least, this patch needs a Fixes tag.

regards,
dan carpenter

Re: [PATCH v3 08/10] staging: octeon-ethernet: support of_get_mac_address new ERR_PTR error

[Petr Štetiar]

Dan Carpenter <dan.carpenter@oracle.com> [2019-05-03 13:34:56]:

Hi,

> On Fri, May 03, 2019 at 09:56:05AM +0200, Petr Štetiar wrote:
> > There was NVMEM support added to of_get_mac_address, so it could now
> > return NULL and ERR_PTR encoded error values, so we need to adjust all
> > current users of of_get_mac_address to this new fact.
> 
> Which commit added NVMEM support?  It hasn't hit net-next or linux-next
> yet...  Very strange.

this patch is a part of the patch series[1], where the 1st patch[2] adds this
NVMEM support to of_get_mac_address and follow-up patches are adjusting
current of_get_mac_address users to the new ERR_PTR return value.

> Why would of_get_mac_address() return a mix of NULL and error pointers?

I've introduced this misleading API in v3, but corrected it in v4, so it now
returns only valid pointer or ERR_PTR encoded error value.

Just FYI, changes for staging/octeon are currently at v5[3].

1. https://patchwork.ozlabs.org/project/netdev/list/?series=105972
2. https://patchwork.ozlabs.org/patch/1094916/
3. https://patchwork.ozlabs.org/patch/1094942/

-- ynezz

Re: [PATCH v3 08/10] staging: octeon-ethernet: support of_get_mac_address new ERR_PTR error

[Dan Carpenter]

On Fri, May 03, 2019 at 09:07:30PM +0200, Petr Štetiar wrote:
> Dan Carpenter <dan.carpenter@oracle.com> [2019-05-03 13:34:56]:
> 
> Hi,
> 
> > On Fri, May 03, 2019 at 09:56:05AM +0200, Petr Štetiar wrote:
> > > There was NVMEM support added to of_get_mac_address, so it could now
> > > return NULL and ERR_PTR encoded error values, so we need to adjust all
> > > current users of of_get_mac_address to this new fact.
> > 
> > Which commit added NVMEM support?  It hasn't hit net-next or linux-next
> > yet...  Very strange.
> 
> this patch is a part of the patch series[1], where the 1st patch[2] adds this
> NVMEM support to of_get_mac_address and follow-up patches are adjusting
> current of_get_mac_address users to the new ERR_PTR return value.

Basically all the patches need to be folded together otherwise you're
breaking git bisectibility.  Imagine that we just apply patch #1 right?
Then all the callers will be broken.  It's not allowed.

regards,
dan carpenter

[PATCH v3 09/10] ARM: Kirkwood: support of_get_mac_address new ERR_PTR error

[Petr Štetiar]

There was NVMEM support added to of_get_mac_address, so it could now
return NULL and ERR_PTR encoded error values, so we need to adjust all
current users of of_get_mac_address to this new fact.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---
 arch/arm/mach-mvebu/kirkwood.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-mvebu/kirkwood.c b/arch/arm/mach-mvebu/kirkwood.c
index 0aa8810..903a4cb 100644
--- a/arch/arm/mach-mvebu/kirkwood.c
+++ b/arch/arm/mach-mvebu/kirkwood.c
@@ -92,7 +92,8 @@ static void __init kirkwood_dt_eth_fixup(void)
 			continue;
 
 		/* skip disabled nodes or nodes with valid MAC address*/
-		if (!of_device_is_available(pnp) || of_get_mac_address(np))
+		if (!of_device_is_available(pnp) ||
+		    !IS_ERR_OR_NULL(of_get_mac_address(np)))
 			goto eth_fixup_skip;
 
 		clk = of_clk_get(pnp, 0);
-- 
1.9.1

[PATCH v3 10/10] powerpc: tsi108: support of_get_mac_address new ERR_PTR error

[Petr Štetiar]

There was NVMEM support added to of_get_mac_address, so it could now
return NULL and ERR_PTR encoded error values, so we need to adjust all
current users of of_get_mac_address to this new fact.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---
 arch/powerpc/sysdev/tsi108_dev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/sysdev/tsi108_dev.c b/arch/powerpc/sysdev/tsi108_dev.c
index 1f1af12..2e54405 100644
--- a/arch/powerpc/sysdev/tsi108_dev.c
+++ b/arch/powerpc/sysdev/tsi108_dev.c
@@ -105,7 +105,7 @@ static int __init tsi108_eth_of_init(void)
 		}
 
 		mac_addr = of_get_mac_address(np);
-		if (mac_addr)
+		if (!IS_ERR_OR_NULL(mac_addr))
 			memcpy(tsi_eth_data.mac_addr, mac_addr, 6);
 
 		ph = of_get_property(np, "mdio-handle", NULL);
-- 
1.9.1